Multidisciplinary and multifidelity optimization for twin-web turbine disc with asymmetric temperature distribution

Abstract

While having been proven its significant advantage in losing weight, twin-web turbine disc (TWD) is known to be the novel stage of development in the area of high-pressure turbine discs. There is a significant axial temperature gradient which should be taken into consideration for the asymmetric web structure to obtain the optimal shape of TWD. An expensive three-dimensional fluid-thermal analysis should be introduced and executed to obtain accurate temperature distribution. A kind of multidisciplinary and multifidelity optimization procedure is proposed for the simultaneous combining of two obvious advantages with the low cost of axisymmetric strength analysis and the high fidelity of three-dimensional fluid-thermal analysis and strength analysis. It is executed under the support techniques, including zero circumferential elasticity modulus method at the non-axisymmetric region during axisymmetric strength analysis and inverse distance weighted method with traversing searching radius. A supporting ring with double sides locating mode at the disc hub is designed to avoid two webs being close to each other and provides the inlet for the cooling gas into the inner cavity. The optimization result demonstrates that the proposed method is capable and has an efficient benefit due to the low-cost computing procedure for obtaining the optimal shape of TWD with asymmetric temperature distribution.